Still burning oil?

-
MopaR&D

MopaR&D

Nerd Member
Joined
Jan 4, 2008
Messages
5,768
Reaction score
3,256
Location
Augusta, GA
Hey guys, my 318 in my Duster is still burning some oil on startup, and I just replaced all the valve stem seals. I did the "ghetto" blowby-check trick where you pull off the PCV valve and breather then feel the holes while the engine is running to see if there is lots of blowby escaping, and there was hardly even a whisper of air, so I think my rings are good (plus it only has 109,000 miles on it).

What else could I check? I think I heard somewhere that you can get blue smoke if you don't replace the breather with a clean one, is that true?
 
Loose valve guide can cause it even if the seals are good. 109,000 miles is enough for them to be loose. First thing I'd check is the torque on the intake manifold bolts. Most of the stock 318's if not all had steel shim gaskets and it could be seeping past them. If you didn't have any blow by I doubt the breather filter could affect it.
 
Hmm, I tried to wiggle some of the valves when I was replacing the seals and none of them really moved at all. I was getting some oil seepage out of one of the intake manifold bolts and I have some new gaskets in the box, I'll probably just replace them tomorrow.
 
I don't know, I got a set of Fel-Pro ones and the ones for the intake valves were positive I think, but the ones for the exhausts were umbrella.
 
I kinda doubt they were pc seals if they were fel-pro's but they could have been. I had a set of Fel-pro's that looked similiar to pc seals but weren't. They were just a smaller version of umbrella seals. Either way those old umbrella seals still work fine too. I've used them on stock heads and they always work fine if the guides are in good shape. They do get hard after time unlike the pc seals. But I've also seen pc seals worn out just as fast as umbrella seals get hard so it can go both ways. In any case if the guides are loose no seal will stop oil seepage totally.

I'm not positive but I think you have to have the guide cut down to accept pc seals anyway so if your guides are stock they probably won't accept them. I won't swear to that but I know my 340X heads were machined and they accept pc seals only now. The umbrella type would probably not seal good because they'd be sloppy fitting.
 
I'm not positive but I think you have to have the guide cut down to accept pc seals anyway so if your guides are stock they probably won't accept them. I won't swear to that but I know my 340X heads were machined and they accept pc seals only now. The umbrella type would probably not seal good because they'd be sloppy fitting.[/QUOTE]

Yes that's correct fishy.
 
If you can get a leakdown tester and an air compressor you can find out very quickly what is worn or causing oil burning. Most racers will tell you that a toolbox isn't complete without 'em.
 
Yeah, well, I do want to do that, but I don't have the money right now. I'm really thinking it's the intake manifold, because when I cold start it and let it fast idle it runs with no smoke for a couple seconds, then the blue smoke starts coming out the exhaust (I'd imagine from vacuum pulling oil from the valley into the intake). I then rev it a couple times and a small puff comes out on each rev, but once I start driving it around and it warms up a couple minutes it's gone. I also get some oil seepage from one intake manifold bolt that forms a small pool of oil on the manifold.

One other thing, on my last oil change I added a good amount of STP additive (the thick syrupy zinc stuff) to protect my cam and lifters, and the smoke did get worse a little while after that. Could that have done something?

I also really doubt it could be my rings; I mean seriously, it's a stock 318 2-bbl. with 109,000 original miles. Don't these things usually last at least twice as long?
 
I just had an "epiphany"... My engine has been acting like it has a vacuum leak (light stumble off idle, some annoying vibrations once in a while when cruising), and I just realized that might be from a bad intake gasket; wouldn't that cause the engine to suck in air (and oil) from the valley?
 
At 109K miles it could be rings and that depends alot on storage conditions. I'd bet that you're on the right track with the intake leak guess. Head and intake gaskets take a beating from the heating and cooling cycles the engine goes thru. Makes it worse when the engine has been sitting long enough to dry all the gaskets.
 
See, the engine was in good condition when I got it though and the seller (who sells a lot of classic cars through eBay) assured me the engine was in good condition and still had a lot of miles left on it. Now I don't think what he said was gospel, but I don't think he was lying either because he did know what he was talking about (for the most part at least). Also just thinking about the history of the car, it was first owned by a lady in California (dry there, isn't it?) who brought it with her here to Colorado, which is even drier. So I don't think the car really sat too much; it does only have 109,000 miles on it since 1970, but it must've been driven a decent amount.
 
Actually 109,000 miles for a 38 year old car is very low mileage. Heck my wifes 2001 Grand Prix has 101,000 on it. 109,000 miles isn't very many miles for a good old 318 either. I've seen them go 200,000 plus miles without needing rings. Allot depends on how they were maintained though. If the oil was changed regularly it should be fine. If it was done like a boss I had back when I was young that believed oil never wore out and never need changed it's a bad deal. The gaskets could very well be the problem and is where I'd look next since you've already replaced the valve seals. Back in the 80's I had a buddy that owned a 76 Fury with a 318 and the head gaskets started leaking coolant into the engine. We replaced the gaskets and he ran it for another 100,000 and never had any more problems. If your considering tearing it down to replace the intake gaskets you might as well just go ahead and pull the heads because if the intake gaskets are leaking the head gaskets are probably not far behind.
 
Oh jeez, I don't think I have time to pull the heads. Hopefully the head gaskets will last at least another 2 weeks until I get my first paycheck :burnout: :cheers:.
 
Hmm, sounds like a carb problem with the temporary blue smoke, my slanted dart did that when i put a two barrel on it. it was embarrassing sometimes :/ well anyways it was just running a little too rich till it warmed up and then it was fine. As for the oil im not sure :/
 
Well, the manifold's sitting out there apart from the engine, just haven't been able to finish what I started. Need some more black RTV too, definitely did not come with enough in the gasket set.

Jeez, a full-time job noon to 8, then studying for my SAT re-take this Saturday... Not my kind of summer (except for the paycheck in two weeks :cheers:).
 

Got the new gaskets on and drove it around yesterday and today, and I think the blue smoke's gone. I still want to try out my neighbor's compression tester though and see if I do have bad rings (which I doubt, but doesn't hurt to double check).
 
You must log in or register to reply here.
-
Back
Top Bottom